Infrared & Terahertz Material
Float Zone Silicon (FZ-Si)
FZ and high-resistivity FZ silicon optics specified for your operating band
Float-zone silicon is a distinct growth grade for infrared optical components. Specify FZ-Si when the growth method matters, or HRFZ-Si when high resistivity is also required. Send your drawing, operating band and finished thickness so the material, coating and inspection requirements can be reviewed together.
Is this material right for your application?
Use When:
- Your drawing specifies float-zone growth.
- Oxygen-related absorption is a design concern.
- A far-IR or THz design requires specified HRFZ material.
Avoid When:
- Visible-light transmission is required.
- FZ is assumed to mean high resistivity automatically.
- Transmission has not been checked at the finished thickness.
Consider Alternatives:
- Silicon (Si) for conventional optical silicon requirements.
- Germanium for selected MWIR/LWIR designs.
- Chalcogenide glass for grade-specific infrared lens designs.
Explore Related Optical Materials
Silicon (Si)
Germanium (Ge)
Chalcogenide Glass
Material specifications and frequently asked questions
FAQ
What makes float-zone silicon different?
It is a distinct growth grade with lower oxygen content than CZ silicon. Specify the growth method explicitly.
Is float-zone silicon always high resistivity?
No. HRFZ and a minimum resistivity must be specified separately.
Can I use it in the LWIR?
Only after checking the selected grade and thickness against the required band. FZ does not remove lattice absorption.
What do you need for quotation?
FZ/HRFZ designation, resistivity, conductivity type, drawing, wavelength band, coating, quantities and inspection requirements.
Can generic silicon stock be substituted?
Only with confirmed growth method, resistivity and performance. This page does not classify ordinary silicon stock as FZ.
Can I specify HRFZ for THz?
Yes, include the THz band, thickness and resistivity, then request grade-specific performance review.
Why are there no generic transmission graphs?
A single curve would conceal grade and thickness differences. The reference PDF includes comparative data; use agreed data for the finished component.
Will I receive a material certificate?
Include certification and traceability requirements in the RFQ so scope and availability can be confirmed before ordering.